<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div {
            width: 150px;
            height: 300px;
            background-color: pink;
        }
    </style>
    <script src="jquery.min.js"></script>
</head>

<body>
    <button>显示</button>
    <button>隐藏</button>
    <button>切换</button>
    <div></div>
    <script>
        $(function () {
            $("button").eq(0).click(function () {
                $(`div`).show(1000,function () {
                    $(`div`).css(`backgroundColor`,`lime`)
                })

            })

            $("button").eq(1).click(function () {
                $(`div`).hide(1000)

            })

            $("button").eq(2).click(function () {

            })
        });
    </script>
</body>

</html>